// TODO(b/246310765): This doesn't fully handle recursion.
      if (!use_count[arg.getArgNumber()]) unused_args.set(arg.getArgNumber());
    }

    EraseReturnOperands(region, unused_results);
    func.eraseResults(unused_results);
    func.eraseArguments(unused_args);

    args_to_erase.insert(std::make_pair(op, unused_args));
    results_to_erase.insert(std::make_pair(op, unused_results));